Moving too fast!

So I recently reconnected with a old middle school buddy of mines. I'm 21 btw so it's been a while because we didn't go to the same high school. Anywho we've hung out twice and he's a great guy, but now he's talking about being in a relationship and we've only been talking for a couple of days. I just got out of a serious relationship not too long ago, and I'm not sure if I'm ready for another one just yet. What should I tell him?